Whisker shrimp or just a really big ghost shrimp?

[The endler guy]

It’s something like 1-1.5 inches

[Odd Duck]

I’m not an expert but whisker shrimp have fairly significant pinchers on extra long legs that reach toward the front.  I don’t think they’re on the first set of legs, though, I think they’re on the second or third set of legs?  I can’t quite tell from your pic if the second set has bigger pinchers and definitely don’t see them on the first set of legs.  You’re shrimp’s legs are not as prominent as the pics I’ve seen but there could have been an injury that temporarily reduced the size of the big pinchers through a couple molts.  Plus there’s more than one species called “whisker shrimp” and more than one species called “ghost shrimp” which can make it much harder to tell.

All that said, I would watch behavior closely but I certainly don’t see the obvious identifiers of whisker shrimp that I remember in your shrimp.

[The endler guy]

On 6/2/2023 at 4:11 PM, Odd Duck said:

I’m not an expert but whisker shrimp have fairly significant pinchers on extra long legs that reach toward the front.  I don’t think they’re on the first set of legs, though, I think they’re on the second or third set of legs?  I can’t quite tell from your pic if the second set has bigger pinchers and definitely don’t see them on the first set of legs.  You’re shrimp’s legs are not as prominent as the pics I’ve seen but there could have been an injury that temporarily reduced the size of the big pinchers through a couple molts.  Plus there’s more than one species called “whisker shrimp” and more than one species called “ghost shrimp” which can make it much harder to tell.

All that said, I would watch behavior closely but I certainly don’t see the obvious identifiers of whisker shrimp that I remember in your shrimp.

That’s what I thought, I even asked the employee at the shop and he said they didn’t have any (they are trying to get them in because they can live with larger fish) 

 

I just wasn’t sure because THATS ONE DAMB BIG SHRIMP!!!

 

I am try to rule out candidates for why a ton of my fish are dying 

[Odd Duck]

Google says ghost shrimp can be 1.5”?

[Torrey]

My female P paludosus get up to 1.75", males are a little smaller and a lot skinnier.

If you want more pics of tank bred P paludosus to compare to, let me know. They are a great little North American native, and I have never caught them (or had any other evidence) of them catching fry.

 

Now, Macrobrachium lanchesteri (whisker shrimp)  have very large, very strong pincers on the second set of pereiopods (walking legs) especially males 

The first set of pereiopods have smaller pincers (chelipeds) that are used to eat.

P paludosus have small chelipeds on the first 2 pairs of pereiopods for eating and in the females for moving fertilized eggs to the pleopods (swimming legs) for incubation. P paludosus also have distinctive orange bands at the base of their feelers and front legs, in addition to a reddish, or reddish orange, dot on each exopod (outside sections of the tail)

Young Macrobrachium can be difficult to distinguish from P paludosus, until the second pair of pereiopods develop the larger pincers.

 

M lanchesteri *can* be identified by the lack of the orange markings that P paludosus have, but there are other Macrobrachium that have been known to mimic the coloring of P paludosus.

If it's eating your fry, I would say a young Macrobrachium, but hard to know for sure which species. I think there's over 200 globally.

One can grow to over 30 cm😶

 

[The endler guy]

On 6/2/2023 at 8:48 PM, Odd Duck said:

Google says ghost shrimp can be 1.5”?

Yay but this is one stinking big boi!!!!

 

it is a female so maybe that’s why